Mat Board Center, High Quality Pack of 25 Set 8x10 Assorted Mix Colors White Core Picture Mats Mattes Matting for 5x7 Photo with Backing and Clear Bags High Quality Set of 25 pieces of 8x10 Picture Mats for 5x7 Photo with backing boards and bags The opening size is 4.5"x6.5" for 5x7 print. Color: Mixed color The re-sealable adhesive strip of the clear bag is below the opening of the bag instead of on the flap. This item comes with the 25 pre-cut mats, 25 backing boards and 25 clear bags. The mats are beveled cut with white core and 4-ply thick (about 1.4 mm or 1/16 inch), The backing is white on both side.